Closely-coupled processors or hardware resources will likely become widely available within the near future. Examples of such closely-coupled processors (or hardware resources) may include additional processors, threads in a particular processor, additional cores in a central processing unit, additional processors mounted on the same substrate or board, and/or such devices provided within computers connected by a network fabric into a cluster, a grid, or a collection of resources.
Certain computations (e.g., parallel processing or parallel programming) may benefit from the availability of such hardware resources. For example, a complex simulation may run faster if the simulation is divided into portions and the portions are simultaneously run on a number of processing devices in a parallel fashion. Parallel computing arrangements may include a controller that determines how an application should be divided and what application portions go to which parallel processors. For example, a host computer that is running a simulation may act as the controller for a number of parallel processors.
Parallel processors may receive instructions and/or data from the controller and may return a result to the controller. Some parallel processing language constructs provide lexical context, associated with multiple processes, in a single process. Other parallel processing language constructs support distributed processing, but may fail to provide control over where data is stored. Still other parallel processing languages can only call functions in parallel.